The ringbuf used to fill up and the recv interrupt would block CP.
Now it'll disable the interrupt until we have enough room in the
ringbuf.
Fixes#6678
* Fixes#6221 - C3 hang on `import wifi`. Enabling the WiFi PHY was
disabling USB. Now boards that use it set CONFIG_ESP_PHY_ENABLE_USB
explicitly.
* Fixes#6655 - Allows pasting into the web serial page. Fixes reading
more than 0xf bytes at a time.
* Fixes#6653 - Fixes web socket encoding of payloads >125 bytes. Can
happen when printing a long string.
* Fixes C3 responsiveness when waiting for key to enter REPL. (It
now correctly stops sleeping.)
* Disables title bar updates when in raw REPL. Related to #6548.
* Adds version to title bar.
It had a tight 5ms timeout before that caused some characters to
drop. Now the wait is longer and reset after a successful transmit.
This follows what MicroPython does.
Fixes#6220
Scott Shawcroft